Cedar Creek
Ecosystem Science Reserve

Insects of Cedar Creek



(Pond Skimmers)

(Table of Species)

     The Pond Skimmers (91 NA spp) are primarily southern in distribution and frequent quiet waters of ponds and marshes.   They range from small to large and many have patterned wings. Larvae are either prettily-patterned climbers in submergent vegetation (eg. Leucorrhinia) or hairy, dark, bottom sprawlers (eg. Libellula) in mucky substrate. Most spend only one year as larvae and overwinter in this stage, but species of Sympetrum overwinter as diapause eggs. Minnesota reports 30 species in the genera Celithemis (2), Erythemis (1), Ladona (1), Leucorrhinia (6), Libellula (3), Nannothemis (1), Pachydiplax (1), Pantala (2), Perithemis (1), Plathemis (1), Sympetrum (8), Tarnetrum (1), and Tramea (2).  27 species have been collected at CCESR.  This large family will be considered chronologically.

     Five species of small black Leucorrhinia emerge from ponds and marshes from mid-May throughout much of June. Leucorrhinia intacta (Johnny white-face) is the most ubiquitous; L. frigida emerges abundantly from Beckman Lake and a few other ponds and marshes as do smaller numbers of the delicate red-and-black L. hudsonica. L. proxima occurs most abundantly in marshes in open woodland, and L. glacialis is a rare species of Beckman Lake. These species have become rare by late July.

     Libellula is another large genus containing medium to large robust species often with patterned wings. Larvae are dark bottom sprawlers, and adults are on the wing from mid-May to mid-August. Libellula quadrimaculata is common in permanent marshes and Libellula (Ladona) julia emerged abundantly from Fish Lake in late-May and early-June. The White-tail, Libellula (Plathemis) lydia, and the 10-Spotter, Libellula pulchella, are common along Cedar Creek and the shoreline of Cedar Bog Lake. The Widow, Libellula luctuosa, is becoming more common on Fish Lake.

     A motley assembly of mid-summer Libellulids includes: Nannothemis bella, a tiny dragonfly inhabiting the sphagnum bog margin of Beckman Lake; the orange-and-brown winged, Celithemis eponina and the blue-abdomened Erythemis simplicicollis on Fish Lake. Celithemis elisa, Perithemis tenera and Pachydiplax longipennis are infrequent visitants to the Lake.

     By late June species of Sympetrum have begun to emerge, and during August and September, Sympetrum and Aeshna are the two prevalent genera encountered. Sympetrum species are small, yellow, clear-winged species whose males turn bright red on maturity. Of the seven species of Sympetrum collected, the first to emerge is the abundant marsh-inhabiting S. obtrusum. Smaller numbers of S. internum and S. rubicundulum also emerge from these marshes. Many of these marshes dry up in late summer and tandem pairs can be seen dropping eggs on the dry substrate where they will not hatch until the following spring. S. danae is an uncommon black species of permanent marshes. The colorful S. semicinctum emerges from Cedar Bog Lake in July as does S. costiferum from Fish Lake. Last to emerge in August is S. vicinum from Beckman Lake and other smaller ponds.

     Tarnetrum corruptum is another migrant that appears in late April and produces a new generation in some of the Area's artificial ponds. These emerge and fly south in September. Similar in life style are the 'Tramp' species Pantala flavescens, Pantala hymenaea, Tramea onusta and Tramea lacerata. Adults arrive  in mid summer from whereabouts unknown and a new generation rapidly develops in the warm waters of small ponds on the Area.

webmaster@cedarcreek.umn.edu Last updated May, 2000